Farm Aid, the annual benefit concert for American farmers organized by Willie Nelson and John Mellencamp, will touch down Sept. 9 at Randall's Island hard by Manhattan, organizers announced today. This year's lineup includes Nelson, Mellencamp, Neil Young and Dave Matthews.

Nelson and Mellencamp joined New York Mayor Michael Bloomberg at Union Square's renowned Greenmarket. The trio took a quick walk through the booths and munched snap peas for the cameras before holding a news conference about this year's show.

"This will be the first Farm Aid that provides 100 percent homegrown food at the concert," Mellencamp said. Acknowledging the Greenmarket, Nelson said, "This is a great example of what can be done in the big cities."

Farm Aid, which is in its 22nd year, will dovetail with a new biofuel initiative in New York. Beginning next summer, 30 percent of the city's heating oil purchases will be required to contain 5 percent biofuel, with a goal of reducing greenhouse gas emissions by 30 percent by 2030.

Nelson was one of the first biofuel champions in the music world and recalled being puzzled when his wife first told him she was interested in purchasing a biofuel-compatible Volkswagen Jetta.

"I thought she might have finally found my Maui stash," Nelson joked. "Biodiesel is the future. There's a huge demand out there -- now we need to increase the supply."

Bloomberg, who joked that he'd written a song called "Mamas, Don't Let Your Babies Grow Up To Be Mayors" with Mellencamp and Nelson on the latter's tour bus, said the September concert is expected to pump $13 million into the city's economy.

Backstage after the press conference, Mellencamp told Billboard.com that although Farm Aid still has major hurdles to clear in its efforts to aid family farmers, he is touched by what has been accomplished so far.

"The most amazing thing I've ever seen was when family farms were hit really bad in the early ¤'90s," he recalled of the crop devastation, increase in produce imports and falling prices during those years. "We were able to provide mental health services for farmers who were on the verge of suicide; a phone call, or a couple of counseling sessions."

Farm Aid's mission includes supporting family farms, changing the system of industrial agriculture, advocating fair prices and encouraging people to buy locally grown food that is organic and humanely produced. During its history, it has raised more than $30 million.

Last year's concert was in Camden, and Matthews' acoustic set and profession of love for family farms were among the highlights. The lineup last year included Matthews, Nelson, Young, Mellencamp, rock legend Jerry Lee Lewis, Shelby Lynne, activist rocker Steve Earle and Alison Moorer (Earle's wife and Lynne's sister), and the Calhoun Twins. Earle and Moorer live in New York, and could easily join this year's lineup.

"We're so happy that y'all have invited us, Farm Aid, to New York City," Nelson said. "Probably more people eat around here than anywhere in the world."